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Re: 1.7.7 on Windows 7: can't write to removable disk


On 2/21/2013 5:55 PM, Latchen McKinney wrote:
On Jan 11 15:55, Corinna Vinschen wrote:
On Jan 11 15:51, Corinna Vinschen wrote:
On Jan 10 10:40, tomas@datasupporten.se wrote:
Hello.
I'm trying to write a disk image to a compact flash card with dd, but I
get the error:
"dd: writing to /dev/sdj: Permission denied"

Apart from the CF-card, I also tried a USB-stick with the same results.
I'm logged in as administrator.

Please have a look into http://support.microsoft.com/kb/942448 first.


[...listening "De-Loused In The Comatorium" while waiting...]

Finished reading? Ok.

That's quite a serious restriction starting with Vista.  If I destroy the
filesystem on one of my sd cards under Linux, I can then overwrite it
with dd under Cygwin.  However, if that dd call created a valid
filesystem on the sd card, the next write fails again.  For some reason
it does not help to unmount the filesystem on the drive via the "Disk
Management" MMC snap-in, despite the claim in the aforementioned
article.

The solution I just checked in to Cygwin is rather complicated, but
I really tested this a couple of hours now, and I didn't find any
other solution.

I forgot the disclaimer:


Please test the next developer snapshot from http://cygwin.com/snapshots/

Update: I checked in a revised version of the patch. The code from yesterday tried to lock all partitions at open() time at once, which is hardly minimal-invasive. It would even try to lock all partitions if you just overwrite the boot sector. With the new code, a partition lock is only triggered on-demand. As soon as a write() call fails with "Access denied", it searches the partition table for a partition which overlaps with the current write position and then tries to lock only that partition.

Hello!

I am curious if this patch was included in the live build of cygwin. I use dd for archiving and making new copies of floppy disks from images, and I can no longer do that in Windows 7. I, too, get the error message:

"dd: writing to /dev/fd0: Permission denied"

Cygwin 1.7.7 is very old and the thread you reference is over 2 years old. The current version of Cygwin is 1.7.17. If you're not up-to-date, try updating. If you are and you're having problems, please read and follow the problem reporting guidelines found at the link below for any follow-up to this list.

Problem reports: http://cygwin.com/problems.html

-- Larry

_____________________________________________________________________

A: Yes.
> Q: Are you sure?
>> A: Because it reverses the logical flow of conversation.
>>> Q: Why is top posting annoying in email?

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